Put pot on floor (2x2 spaces)
Put items in pot (any item)
Put gas cooker on gas can (=> 1x2 spaces)
Put pot on gas cooker and can (1x2 spaces + 2x2 spaces = 1x2 spaces)
4 spaces storage become 2 spaces in inventory
The crazy part is, large gas can plus cooker and pot should actually be at least 6 spaces (2x3) according to any sensible logic.